


Octobill

by BurnerAccount



Category: Gravity Falls
Genre: AKA Octobill, Consentacles, M/M, Octopus Bill, Older Dipper Pines, Tentacle Sex
Language: English
Status: Completed
Published: 2016-10-05
Updated: 2016-10-05
Packaged: 2018-08-19 16:46:15
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 6,107
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/8217565
Author URL: https://archiveofourown.org/users/BurnerAccount/pseuds/BurnerAccount
Summary: You know exactly what this is.





	

It’s three in the morning. Three. In the morning.

Dipper blinks slowly, shoes making soft clacks on the tile as he trudges, begrudgingly, through the main exhibit hall.

The tanks are faintly illuminated, casting gentle blue light around the empty aquarium building. He accepted a flashlight, but didn’t bother to turn it on. Not like it’ll do much good, he knows that from experience.

It’s eerie, being so alone in the usually busy building. Everything so quiet. Almost serene. It’d be calming - if he wasn’t so grumpy at the ungodly hour he was called in. He wanted to roll over and ignore it, then, hearing what happened - Ran a hand through his hair, cursed at everything, and rolled out of bed with a long, frustrated groan.

Bill’s out.

Again.

It’d be nice to have backup, but the security guards won’t come anywhere near the area, considering the situation. There won’t be any video recordings, the cameras were taken out, first thing. And they _still_ don’t have a working antivenom for this creature. If Bill caused just a little more trouble… they might try to dump him back in the ocean. But they can’t _prove_ anything.

Accidents happen around dangerous creatures, but Bill’s in a class of his own.

 _Octopodinae Sapiens._ Little bit human - on top, at least, and the rest - obvious. Though he only has _seven_ tentacles, they’re just as clingy as a full set of eight. He’s the crown jewel of this entire place, he draws one hell of a crowd. The only specimen in ‘captivity’.

Dipper rolls his eyes at the thought, looking around. He can smell saltwater, and- he glances down. Yep, puddles. Trailing streaks of water, where the tentacles slid along the tile. He’s in the right area, Bill hasn’t wandered too far away this time.

There’s no way someone could _capture_ Bill. Even if it wouldn’t be wrong, on multiple levels, to keep a sentient being trapped against their will - Bill breaks out whenever he wants, on the slightest whim.

He hasn’t run off yet. No surprise there. Bill loves the attention, the free food, the adulation. And  another thing.

Dipper knows, with absolute certainty, that Bill considers everyone _else_ the _‘exhibit’_.

He’s a big fan of people-watching. And talking. Also, he’s a freaking huge half-octopus guy, who either doesn’t care much about morality, or just likes scaring the shit out of humans, and saying things that make people start crying if he gets to chat to them for too long.

Losing Bill isn’t the problem, though the aquarium would miss the cash flow. The _biggest_ problem with Bill is doing damage control, and that’s _Dipper’s_ job.

Hooray.

He rubs at his face with one hand, stalking over to rest on one of the benches by the wall. He clears his throat, leaning back and setting down his unused flashlight.

“Oh no, look at me,” Dipper says, flatly. “All alone in here. Entirely vulnerable.” He doesn’t look around, just sits there, in the dark, and folds his arms. “Gee, I sure hope that someone doesn’t _sneak up on_ me.” Dipper shuts his eyes, leaning back against the wall.

From somewhere across the exhibit hall, there’s a soft huff, and Bill’s voice.

“Yeah, yeah, wring all the fun out of it, why don’tcha.” He sounds a little disappointed. “You’re such a killjoy sometimes.”

Dipper still can’t tell where Bill is, exactly, and there’s no point in looking. Likely as not, the bastard’s camouflaged. Lighting up the place won’t help, and he’s been through this routine before. Hell, it’s how they _met_. He’s not going to know where Bill is until he strikes.

Ambush predators. Honestly.

Dipper wasn’t supposed to be Bill’s quote-unquote ‘handler’. Volunteering at the aquarium looked good on his resume, and it was fun, too. He was spending a few hours a week there while getting his degree, pretty standard, but, no. It couldn’t be simple.

The incredibly unruly, recently ‘acquired’ Bill decided he liked the look of Dipper, and _demanded him_ , on threat of _biting_ anyone else.

Turns out you can get hired, on the spot, with a really high salary, if there’s something very valuable only you can do. Also if there’s one massive tentacle dangling your boss around by the collar of her shirt, and three others wrapped around yourself, slick and clinging tight.

The suckers on Bill’s tentacles left hickeys. They _always_ leave marks, even though Dipper knows Bill’s got better control than that.

At least this ‘game’ Bill likes to play isn’t going to hurt anyone when Dipper’s there to draw him out. Bill’s nearly given two dozen guests heart attacks when he popped up in the early morning, and made _tons_ of kids run screaming in terror. Better Dipper gets jumped by Bill, now, in the middle of the night, rather than letting him wait around until morning to get his thrill from terrorizing the regular populace.

Dipper’s job sucks.

“C’mon,” Bill says plaintively, and slightly coy. His voice echos through the atrium. Dipper squeezes his eyes shut tighter. “Make it more of a game! It’s not the same when you just _sit_ there!”

Dipper, reluctantly, stands. Though he takes in a slow breath, lets it out, and grumbles something unflattering about Bill before he starts walking around.

Nothing weird about this here. He’s just. Some guy that’s going to be snagged into the inescapable grasp of an intelligent predator, at any moment.

In _theory_ … if Dipper spots Bill first, he wins the round. He’s managed it _once_ before, and he doesn’t think he’ll manage it now. But it keeps Bill entertained, and he’s that much easier to deal with the next day. Besides. He’s used to it.

He walks through the atrium, and - well, there’s no reason he should make this easy for Bill, either - kicks his shoes off as quietly as he can, leaving them behind as he listens closely. His feet are silent now on the tile.

“Now that’s the spirit!” Wherever Bill is, he sounds cheerful. “You gotta drop by more often,” Weaving in between the standing tanks, Dipper keeps his eyes nearly shut, and concentrates on the sounds around him. “Daytime’s got plenty of humans around, but it just gets so boring when-”

There’s a gentle clatter-

Then a sharp clack against a wall, a very quiet shuffling smack up high, above him - Dipper starts grinning.

Bill found a shoe - probably threw it, once he realized Dipper was evading him - and that’s another bit of information. Dipper’s _got_ this one, for the first time in a long time.

Bill’s on the _ceiling_. He’s not going to _escape_ , but at least he’s prepared for Bill to try get the-

Drop on him.

Dipper hits the ground hard, breath forced out of him as at least a third of Bill’s massive weight hits him from above. His face almost smacks against the tiled floor, but he was prepared, for once, and caught himself.

Bill didn’t land on him directly, but there’s still a hundred pounds of slick, writhing weight crawling up his back, and Bill’s laughing hard - but he’s uninjured

He loosens up, sighing and lying down fully. His cheek presses against the cold floor.

It should be strange, or disconcerting, but it’s so early - slash - late, and Dipper’s tired. And if Bill wanted to take a chunk out of him somewhere, he’s had ample opportunities to do so.

Being Bill’s ‘handler’ sounds way more prestigious than it actually is. Keeping Bill in line seems like a gargantuan task - like convincing the creature to stay would be so difficult - like Dipper has to be the smartest, most clever guy in the place, to keep Bill interested. But it sure as hell has nothing to do with clever cage design, or tricking Bill into staying. He _should_ feel like he’s someone important. Like being able to keep this creature around is some triumph of science.

Dipper feels Bill shuffling off him stickily, chuckling to himself. He keeps lying on his stomach, resting his chin in one hand.

Mostly, Dipper feels like a cat toy. Entertaining Bill when he gets bored, and one thing Bill never gets bored of is catching Dipper - then letting him go, hiding - and catching him again.

“So, did you want to take this somewhere else? Do something else? Literally anything else.” Dipper asks. His eyes are shut, and he keeps lying where he is.

If Bill wants to continue, _he’s_ gonna be the one to put in the effort to make things fun. It’s too _early_ for this.

Dipper will ‘play’ with Bill, sure, it’s - actually a little fun - but this is the wrong time of day. It’s not _even_ day. Bill has been pulling this middle-of-the-night bullshit off and on for three months now, and Dipper’s the only one who can indulge him, and still come out of it in one piece. Or at all.

A soft, consoling sound. “Aw, I like having you around! And nights are so boring! C’mere, kid” Bill says, cheerful as anything.

Dipper lets his head drop, forehead thunking on the tile floor. One of Bill’s tentacles loops around his ankle, tight and firm - but his skin is slick, soft to the touch. Dipper gets dragged backwards, sulking on the wet floor. His shirt pulls up as he’s pulled along.

“You sure are grumpy today,” Bill says, finally releasing him. There’s a quiet, slightly wet sound - he’s moving around, probably in that wiggly way that means he’s grumpy himself.

Groaning quietly, Dipper pushes himself up off the ground, standing and turning to look at Bill.

When he’s splayed out like this, tentacles meandering over the tile, he’s shorter than Dipper. But that’s when he’s spread out. His torso is normal-sized - looking human as anything as he glares, arms crossed. Beneath that, writhing, are his tentacles, the octopus-like bit of him. Long, huge, powerful things, and when he’s not changing his color to blend in to the background… they’re _mostly_ light blue.

Now, neon yellow triangles flare and dull on his skin as his chromatophores work, pulsing in annoyance.

It’s a warning sign - a warning _color_. Bill has yet to bite anyone, but _nobody’s_ gonna risk it.

Except Dipper, who doesn’t have a choice.

“What’s the deal? Usually you’re a little more,” Bill pauses briefly, and there’s soft patting sound as a tentacle taps the ground - “Y’know, into this.”

Yeah, Dipper usually is, but he’s just. He sighs and tries to wipe some of the slickness off his clothing, where Bill touched him.

More than a few unexpected things have come up, as he’s learned about Bill’s behavior, but this newish one’s frustrating, and tiresome. He’s getting so sick of this late-night thing. He wants to get a good night’s sleep. He wants to know what’d keep Bill docile, for once, because in all the time he’s known this creature, he hasn’t found it yet.

“I’m _tired_ , Bill,” says Dipper, finally, letting himself slump. “Do you really have to keep pulling this? You know they call me in whenever-”

“Well, duh,” Bill scoffs, rolling his eyes. He raises himself up, propped up on his squirming lower limbs, looming over Dipper now - Dipper leans back slightly as one tentacle reaches up, sliding up his arm. “How _else’m_ I supposed to get you here at the right time?”

“The right time,” repeats Dipper, staring at his charge. The tentacle on his arm is creeping upwards, rubbing underneath his chin, slick and smooth. He tilts his head back and away. There’s a tight feeling around his thighs -

He shuts his eyes. “ _Arms_ , Bill.”

Bill shrugs slightly, lifting up his human arms, grinning. “Ah, what can I say! They’ve got a mind of their own!” The tight wet grip on Dipper’s thighs loosens. One of Bill’s tentacle arms raises up to wave at his face, suckers and all.

Dipper glares at it, then at Bill, and pushes the thing down with a soft smack of his palm before leaning over, peeling an arm tip-first off his thigh.

Biologically, Bill’s similar to the species he’s named after, though he’s in a different phylum entirely. But his nervous system _is_ spread out widely, his limbs do act without him _intentionally_ making them do stuff. Now that Bill’s noticed, he’s fully capable of pulling away himself - he’s just being a jerk.

Gripping the tip, drawing it off himself like he’s peeling away a bandaid - the tentacle on Dipper’s jeans come away from his right leg, reluctantly. Dipper startles as the one on his _left_ thigh creeps even higher, cupping around his backside - That one gets _ripped_ away, even as Bill shrugs again, looking at another aquarium tank as though it’s fascinating.

What a bastard. Bill’s always a source of irritation. The way things have been amping up, these last couple months, it makes Dipper _dream_ of picking Bill up - impossible, he’s several times Dipper’s weight - and tossing him into the sea again. Also impossible. Dipper would only get _all_ of Bill’s limbs wrapped around him, and dragged along for the ride. Probably drowned, for attempting it.

Dipper’s not certain why Bill’s so interested in him. Or how he’s even still _alive_.

It takes a minute, using both hands, but eventually, he’s free from most of Bill’s groping. There’s still two smooth tentacles curling around Dipper’s ankles, and the third is, surprisingly, not trying cling to him. It’s sliding over his shoulder, around the back of his neck - briefly tickling behind his ear.

Dipper claps a hand over it to _stop_ that. It slides effortlessly under his palm, and the tip taps against his lower lip. Pressing his lips together tightly, he glares- and tenses.

Bill is leaning in very, very close, and smiling.

“How long have I been here again?” Bill pauses, looking contemplative, but doesn’t wait for Dipper to respond. Another arm wraps around one of Dippers - then the other - loose, but clinging tight. Great. More hickeys - “I think we’ve learned a lot about each other! One big, happy, interspecies cultural exchange!”

“Not exactly how I’d describe it.” Though to be fair, Dipper could, _kinda_ consider himself a…  specialist of sorts, with this species-

Bill talks over him blithely,  smiling. “So since you haven’t picked up the _usual_ hints, _here’s_ one that’ll get across to you.”

The limb around Dipper’s neck tightens. Dipper’s dragged forward and with a jolt he realizes he’s on a collision course with Bill’s _mouth._ Dipper kicks out, but that just means Bill gets a grip on his legs again.

He’s going to be _bitten_ , and soon he won’t be able to breathe, he won’t be able to _move_ , then he’s going to choke and _die_ , convulsing- He wishes he’d never encouraged this game with Bill, he shouldn’t have shown up tonight, or any other, he shuts his eyes and feels Bill’s mouth press against his own.

Not… biting.

He _licks_.

Dipper tries to protest, Bill’s tongue slides into his mouth. The muffled sound he makes is startled, because this is- can’t be-

He’s tangled up by Bill completely. Even the human arms have joined in, wrapping around his waist, and that tightening touch on his butt is _definitely intentional._

Drawing back slowly, Bill stares at Dipper with half-lidded eyes. Annoyingly smug. “Get it now?”

“Mmh,” hums Dipper. Bill’s tried for _this_ before, too. There’s a tentacle near the corner of his mouth, stroking his lower lip, and he’s _not_ going to lick it. He’s keeping his mouth shut.

Bill huffs out an annoyed breath. “Don’t be like that!”  His hands roam up Dipper’s back, tentacle releasing his neck only to dip down to take their place - “You think I whip this thing out for just _anyone_?”

Wait, he’s-

One, two, three, four- _Eight_ tentacles, and this one’s a bit shorter, the end of the tentacle lacks suckers, instead strangely tipped -

Oh god, Dipper knows cephalopod biology, Bill’s sentient, of course he’d have this… tucked away, he’s got some sense of decency.

Except around Dipper, apparently.

He can’t help it, he splutters and glares, face feeling hot. “Dude, Bill. _Not_ cool.”

“Least I wasn’t waving it around in front of the guests,” Bill smirks, wiggling his eyebrows.  

“Get that _out of there_.” The thing’s working its way under the back of Dipper’s pants, he struggles. “So this is-” He tenses in Bill’s grip, why this creature’s been- “I mean, you-” Had to bring Dipper around at the _right time_ -

“I thought I was being obvious! Hey, not like I could just jet on over to your place,” Bill says, sounding calm and reasonable, the jerk. His grin is wide and alluring. “Ease up, kid, nobody’s gonna _see_ us, I made sure of that.” Cameras, right, they’re broken. Again, because. This.

Dipper is going to wiggle his way out of here, and tell Bill off, and tell him how impossible and insane and really disturbing and kind of flattering this is.

Bill is lukewarm and slick to the touch, and wherever his arms grip Dipper he’s firm, and strong, underneath the smooth skin. It’s not unpleasant. And. Bill’s said before that he likes the way _Dipper_ feels under his limbs. Strange, and lithe, and - and _hot_.

This is weird. Everything about Bill was already weird, this is a step or two further. Bill shouldn’t want him. They’re nothing like each other. They aren’t even - Well, the parts are totally different, they’d have to work around that and there’s no way that wouldn’t get awkward. Dipper should know, he’s thought of all _kinds_ of ways this exact scenario could go horribly wrong.

Dipper stares.

He doesn’t say anything as the pressure of Bill’s limbs around him pulses, waving their lines of suckers to draw him in even tighter.

He doesn’t say anything when Bill’s human hands start undoing his belt, or when - he shuts his eyes - the clothing slides off his hips, or when a limb slides up under his shirt, the slick, twisting thing searching out his nipple. Moving, though, he can’t help but do that, even though he can’t do much of it.

They feel _weird_ , Bill’s arms. Kind of like tongues, but too slippery. One of Bill’s human hands follows its trail, and when the nail scrapes over Dipper’s nipple, hard, he finally _gasps._

It’s difficult to be certain but at the sound, Bill… seems like he starts clinging less. His limbs rove around, still tight - keeping Dipper close - but more like... exploring.

Dipper already feels all slicked up, and strange, and he’s being not, exactly, prodded all over. More like being _licked_ all over, by the trailing ends of Bill’s limbs. They slide around an elbow, over his neck and shoulders, they weave in between his fingers, there’s no escape and Dipper shuts his eyes tightly, sucking in a breath, and… relaxes into it , though he knows he shouldn’t, it feels good and. And he shouldn’t, really, this is a terrible idea and he’s letting it happen anyway.

Bill’s thrilled, at least.

“Now _that’s_ what I’m talking about,” Bill murmurs. The weight of him as he encircles his captive slowly drags Dipper to the ground, making him lie flat on his back - That heavy pressure, keeping him still but moving all over him, by itself, Bill, above him, _around_ him, his human hands cupping Dipper’s face.

There’s a pause. Bill’s tentacles still. “Hold up a sec, I wanna try this again.”

Dipper has to find his breath again. He gasps softly, licking his  lips - his  mouth feels dry - searchin for the right way to reply, confused -“Try wha-”

Being kissed is still new, and and weirdly gentle, and Bill tastes like the ocean, salt-sweet and delicate, Dipper groans into it-

Oh god.

Between Bill being all over him, and being so relaxed, and all of the limbs Bill has - there is a distinct lack of clothing between them now. Dipper pulls in a shaky breath, eyes closed. Bill shifts around, hauls Dipper around, leaving him kneeling, legs slightly spread.

Dipper squirms, a bit. There’s resistance, he can’t move much. Bill’s holding him tightly around each arm and leg - and the eighth tentacle is creeping downwards over his back, slips between his thighs, and upwards - he makes a small noise as it brushes against him.

“Well, hello there!” Bill slides closer. Human hands run down Dipper’s chest. He’s breathing somewhat rapidly. He peeks an eye open, watching Bill tilt his head. “So this is what all the fuss is about, huh?”

“I-” Dipper glares, he’s feeling hot. Bill’s making it sound like - Dipper’s is _fine_ , and _\- Bill’s_ is obviously more impressive, it’s only a huge tentacle, so he might not know what’s reasonable- Still, though! “Hey, I’m-”

“An excellent specimen, I’m sure,” Bill says dryly. He’s not making eye contact, just looking down, and watching. He presses his thumb against the head, gripping Dipper almost carefully. “Always wondered why you guys called it ‘hard’.”

“That, uh,” Dipper says, weakly. He tenses his legs. The tentacle’s running around his dick now, just below Bill’s hand. It’s very smooth, just short of tight, and though Bill’s not moving his grip it’s getting kind of difficult to concentrate. He searches for something to say and just lets out a strangled-sounding. “Yeah.”

“Hm,” Bill narrows his eyes, humming to himself in thought. He squeezes, carefully. “So I get how this works! Mostly.” He’s starting to look annoyed, though his eighth tentacle slides back over Dipper’s dick, retreating back towards other places- “Cause I’m pretty sure I should get in _there_.”

Crap, the parts are totally unfamiliar to Bill, and it’s great, so far, but Dipper’s worried.

Frankly, he can’t believe this is happening. That Bill is _interested_ in him is insane, but. No, Bill’s _more_ than interested. He’s…

Listened to people talking - he’s likely asked questions, probably really personal ones - he’s been fondling Dipper for months, he’s kissed him, and then went _further_ , and did _more_ , he’s done _research_ for this. He’s been watching. He’s been learning, and in a fucked-up way, flirting with him.

And Dipper…

Hell, he’s seen how Bill can move around so smoothly, and secretively. How nice Bill’s human bit looks - hell, there are websites about this species. And for fuck’s sake, none of _those_ helped, because those were fictional.

Nobody else has felt something so _real_. Dipper’s _had_ Bill wrapped around him, close and wet and prodding. Always touching, everywhere. Bill has a quick wit and a literally dangerous smile, and he’s always _naked_ , _that_ didn’t help Dipper stop thinking about. About. Things.

He’s had more than a few dumb, half-drunk, entirely regrettable jerk-off sessions thinking about this, and now it’s right here surrounding him, and _touching_ him, and Bill’s starting to move his hand, it sends a jolt of alarm and pleasure up his back.

It’s so much _better_ than he thought.

Reality is _also_ more intimidating than fantasy, but Dipper can make sure it stays _reasonable_. He shifts around, rolling his shoulders, testing how much he can move.

“Yeah,” He says again, because apparently he’s completely lost the ability to form coherent thoughts. “Uh. Careful. I mean,” He jerks as the slick tip of Bill’s tentacle - Bill’s weird, writhing dick - brushes against his thigh, stroking upwards - “And just. Careful!” His voice raises in pitch as he tenses.

Bill chuckles softly  “I can go easy on ya. C’mon, I’ve noticed how your species works.” His arm around Dipper’s back squeezes him tighter, and the tentacle slips slowly over its target, back and forth, moving, just slightly. “You’re not as flexible as you should be.”

Dipper shifts in place, letting out a shaky breath.

Okay. Fine. He can deal with that. Bill’s not stupid, he’s done some research. This could be fine.

So far it’s _more_ than fine.

And why is Bill moving like that, running over and over. It’s just reminding Dipper, every second, of what’s about to happen. He’s really, very, uncomfortably hard, and he _wants_ , and he can’t move either away or towards it, he has to wait for _Bill_.

“Oh hey, you do move! A little,” Bill says, happily, sounding just a little short of breath. He has no idea what he’s doing, he’s never touched one before, but he felt the twitch of Dipper’s dick in his hand and now his other hand comes around to join the party. “You really like this, don’tcha.”

Dipper nods, rapidly. He _does_ like it, this has got to go further, or he’s never going to forgive Bill, for offering this and taking it away. He shifts his legs apart more, feeling that slide against him, and tries to relax.

“Just. Take it slow?”

There’s pressure - it retreats, returns. Bill touches him again, and pushes - then stops, and Dipper swears.

Because Bill is always a bastard and now he’s _teasing-_

Bill lets out a soft, almost breathless chuckle. “You made me wait, kid,” He slides a human arm around Dipper’s back, nosing into his neck. “You made me wait…” The squirming, cool-slick thing enters, finally, thicker than Dipper had thought, and Bill sighs, low. “ _So_ long.”

Bill curls around him, using every limb. Dipper’s feeling embraced, all over -

Finding purchase, Bill’s tentacle slips inside. Dipper can’t move much, but he can cling to Bill. It’s slow. And it’s only a small part so far, but it _wriggles._ Wherever Bill learned about how to-

Dipper arches back, gasping suddenly.

Okay, okay. Bill knows what he’s doing.

It’s hitting Dipper inside with each push. It’s slight, for the moment. But it only gets _better_ .The tentacle moves in, and in, so careful, and so _much_.

It keeps pressing, and pushing, adding pressure against Dipper in a _fantastic_ way inside as Bill works his way in. There’s a slow wet stretch, from those short, writhing thrusts, getting deeper each time-

Dipper needs to stop whimpering.

Pressing his face against Bill’s neck is nice. He’s cool but pleasant to the touch, and this way Bill can’t see his face, and he can muffle the sounds he’s making. He takes a deep breath, feeling hot and embarrassed and _good_.

Bill smells like the _ocean_. He’s so smooth and - not quite warm, but his human part is a touch warmer than his arms. His skin is still damp with seawater. Dipper kisses that skin, tongue flickering out. Bill tastes like salt, and something sweet, he’s relentlessly pressing, and pushing, and writhing in _deep_.

Dipper bites down, gently. He worries the surface of that inhuman skin with his teeth, then sucks on it, hard.

It’s about time he made a hickey on this guy. Bill’s left enough on Dipper, this is revenge.

He hears Bill stutter out something. His shoulders shake. He lets go of Dipper’s dick, leaning in and clinging to him, hard, arms wrapping around Dipper. He clutches Dipper close to his chest, hissing softly through his teeth.

“ _You_ ,” Bill mutters, jaw clenched tight. Dipper can’t stop the way his chest heaves, he isn’t panting, really. But he bucks his hips -

He could handle more, he _needs_ more - it’s a constant slipping touch, making his dick twitch with every stroke, full and filling, unending. Every limb around him flexes, drawing him tight against Bill...

“Are so. Fucking,” Bill groans, breathing harder against Dipper’s shoulder. “You're always there, with those _legs, being so cute,_ ” He’s buried deep, now he’s - moving around inside, weirdly, thrusting and, and _pulsing_ , widening then relaxing, a whole range of touch- "Fuck. You're  _tight_."

Even though he’s tangled up in Bill’s arms, Dipper can run his hands down that back, and bite into that neck. It’s a struggle to move but Bill loves it. His limbs writhe at every touch. He’s too distracted to stop Dipper clinging back, stop him from sucking on Bill’s skin.

Scraping his teeth against Bill’s neck and shoulder is so _good_ , with the salt-sweet taste of him on Dipper’s tongue, he wants to mark Bill, in the same way Bill’s left marks, every time.

He pulls back to breathe - admires the way there’s a soft purple blotch, wherever he’s bitten, and he can feel that thing inside him moving with purpose, harder now, smooth and stretching and _deep_.

Dipper’s panting, he tenses up. Bill’s dick is absolutely relentless in how it strokes Dipper inside, never giving him a break - Bill’s going back and forth, and in and out, hell, Dipper’s _about_ to-

“You. _Fucking_...” Bill hisses, his tentacle dick shoves in deeper than before, and squirms, panting against Dipper’s shoulder - “ _Delicious_ little-”

For a startling, heart-stopping moment, Dipper feels those teeth run across his skin. Dangerous, deadly, so close -

Bill shudders. He twists. He pulls his mouth away, biting at the air, eyes shut.

Every other tentacle starts moving, tightening, or releasing, then clinging again, they almost flail - And the one inside Dipper expands, and _throbs_.

The extra pressure is too _much_ , the movement inside, a sharp thump of pleasure - and he shudders, he trembles, he makes a noise he’s not proud of, panting, and comes, shaking, twisting in Bill’s grip.

Because holy _shit_ . There’s so _much_ . Bill has been holding back for _months_ and now it’s finally coming out, as Bill is coming, it sends a long, wet trickle down the inside of Dipper’s thighs. He’s still being touched inside as Bill’s dick squirms around and it’s fucking overwhelming.

Dipper tries to squeeze his legs shut. Bill’s swearing, and clinging, and nosing up against Dipper’s shoulder.

Bill takes in a sharp breath. He slips out, slow. The brief wriggle as he eases away makes Dipper whimper.

At least Bill’s limbs are looser - they drop slowly away, two wrapping around Dipper’s waist, holding close.

Dipper grips onto Bill’s shoulders, breathing hard. Trying to calm down.

Okay, that was nothing like he’d thought it would be. Not… Not awkward. _Intense_.

Bill’s still nuzzling,  slow and damp, though now he lets out a pleased groan.

“Oh man. I needed that,” Bill mutters, straightening back up. He’s grinning, his limbs roll around in lazy waves.

Dipper blinks. “Yeah,” He lowers himself down slowly, sitting on the floor. “I think I noticed.”

He leans up against Bill, feeling tired, and good, and a little gross. It must be funny to Bill, because his chest shakes as he starts chuckling. The tile is cold under Dipper’s legs, and more than a little wet.

The _tile._   

Dipper’s head shoots up. He meets Bill’s eyes. He’s still smiling, wriggling an arm over Dipper’s legs again.

Of course he’s happy, that bastard. Likely he doesn’t care about this in the slightest. He doesn’t have to worry about anything, he just got laid and getting caught doesn’t bother him.

They’re in the freaking _atrium_ and the place is supposed to open in like three hours - Dipper starts, pushing down on Bill’s shoulders as he stands and looks for his pants. That’s in less than three hours, they’ve been at things for a while - And someone’s going to come in here _eventually_ , whether they’re scared of Bill or not.

Researching Bill isn’t supposed to go like this. Usually it’s pretty hands off. Bill likes getting cryptic, likes threatening violence, and _doesn’t_ like being touched. He’s a nasty piece of work, when he’s riled, and the list of humans Bill lets close is even shorter than his temper.

 _Dipper’s_ the Bill-expert, because this creature doesn’t mind _this_ human examining him, he’s never minded - and he loves talking to him. And catching him. Teasing him.  Unlike _everyone_ else, with Dipper, Bill’s -

\- Surging up on his slithering arms, trying to kiss him again. Dipper lets it happen grumpily, then scrambles to get up -

\- Bill’s pretty friendly.

But it’s one thing to be _friendly_ with Bill, and an entirely different thing to be _this_ friendly. Maybe Dipper has good job security, but he doesn’t need _this_ getting out there.

On the plus side, Dipper really _is_ a specialist with this species. Maybe he knows more than anyone else. He even knows a lot more about courtship and mating habits now.

He, uh. Just… collected the data in a really weird way.

“Aw, come back here,” Bill says, coy and a little amused. His arms pull Dipper back in, he stumbles to follow. Relaxed or not, Bill’s clingy, no matter what. He licks a wet stripe up Dipper’s stomach, it makes him jump a little. “Where d’you think you’re going?”

“To get dressed, for one-” Agh, there’s so _little time_. Bill licks again, Dipper buries his fingers in his hair, tensing up. Distractions, nice or not, are not on the table right now. “And, uh,”  He feels his face heat up.  

He looks around. Thank god they’re alone. For all the contingency plans to deal with Bill, this is something he’d _never_ prepared for. Shit, he probably needs to find a mop. Or something. God, where are the towels again.

Bill’s starting to move upwards, he’s at Dipper’s collarbone now.

“Whatever, you’ve got time, stop freaking out,” Bill grumbles. His hands settle on Dipper’s chest. “Stick around for a sec, yeesh.” All his limbs are doing their grumpy type of wriggle again.

Huh. Dipper shouldn’t be surprised. With everything else he knows - he’s getting tangled up again, loosely - Dipper rolls his eyes. Sticking to things is at least one eighth of what Bill does. Probably he wouldn’t call himself one - Blame it on instinct or biology, like he always does, when it gives him an excuse -

Bill loops his human arms over Dipper’s shoulders, and noses against his jawline. It makes Dipper smile.

Fuck the excuses. Bill’s a cuddler.

A _close_ cuddler. Raising himself up more, leaning in _way_ too close- Dipper almost slips under the force. “Bill, you’re _heavy_ .” And this is _ridiculous_ . He’s not sure why he’s having to fight back a laugh, it’s _stupid-_ “C’mon, quit it.”

Bill rolls his eyes, but lets up, only slightly. “It’s always work, work, work with you,”  He says, smirking. “Take some time for pleasure once in a while.”

God, and it is always, always work around Bill. Bill basically _is_ his job, and they’re rarely, you know. Alone like this. Someone else is _always_ watching, with Dipper there as a barrier between themselves and the subject of their research. Bill scares people too much for them to get too close, without something to prevent them-

Son of a _bitch_.

Bill has been escaping so often to _scare people away,_ to seem unpredictable, so that the only person who would be brought into the building like this, alone - Dipper grips onto Bill tighter - he’s been -

Bill’s escapes weren’t that frequent, in the beginning. He didn’t act as intimidating as he could be, dangerous as he is. All of this ramped up over time, and-

It’s so late, and quiet. The dim blue light, the quiet sounds of water - Bill, attentive and affectionate. Being here, alone with Bill, with none of that other bullshit of the daytime, and…It’s almost a little - it’s got good atmosphere for a - Bill _totally_ knows what he’s been doing. In the most jerk way possible.

Well. Shit. _This_ plan was in the works _far_ more than three months ago.

Everything Bill's doing - smiling, acting nonchalant, and casual - it’s camouflage. Hiding the fact that he sunk the better part of a year into setting up this stupid, bizarre, flattering scenario. Bill _totally_ knows what he’s worked this hard to set up. In the most jerk way possible, but....

Good on him, Dipper guesses. A jerk, sure, but he’s got _some_ of the right parts of human courtship down.

Maybe he can follow up on the rest.

Bill laughs. He’s a smug, dickish, inappropriate guy, but he’s sly. He can keep a secret. They don’t have to do _this_ every time, either, it’s.

Some alone time with Bill would be... nice. Dipper’s always wanted to know more about him, Bill loves to talk. He's fun, and weird, and strange, he's a fascinating creature, Dipper could learn all about him, more than anyone. And who the hell would risk bothering them? He has this creature _all to himself_.

Dipper sighs, fondly, shaking his head. He cups Bill’s face in both hands, and…  this is dumb idea. Despite everything, how much trouble this could cause-

“Same time next week?”

Bill leans in, tilts his head. He raises an eyebrow. Dipper takes the invitation, and kisses him soundly.

It’s insane and pleasant, wet and warm. Bill’s inhuman, he’s absolutely crazy, and Dipper is going to learn _everything_ about him.

“Sure thing, kid.” Bill chuckles, drawing away. One of his tentacles slides up over Dipper’s cheek, brushes his hair back, gentle.

Then he winks. “It’s a _date_.”

**Author's Note:**

> Welp, that sure was something!
> 
> Happy Octobill October, everyone.


End file.
